Instructions

1. Arrange a rack in the lower third of the oven and heat the oven to 425°F.
2. Remove the outer leaves from 1 large cabbage. Trim the base of the core to stabilize the cabbage, but leave the core otherwise intact. Cut a 1-inch round off of the right and left sides of the cabbage. Reserve this for another use or discard. Slice the remaining cabbage lengthwise through the core into 4 (about 1-inch thick) rounds or steaks. Arrange the cabbage cut-side down in a single layer on an ungreased rimmed baking sheet.
3. Juice 1/2 small lemon until you have 1 tablespoon juice. Coarsely chop 1/4 cup walnuts or pecans.
4. Prepare the following,adding each to the same small bowl as you complete: Pick and finely chop the leaves from 1 fresh rosemary sprig (about 1 teaspoon). Add 3/4 teaspoon kosher salt, 1/2 teaspoon garlic powder, and 1/4 teaspoon black pepper, and stir to combine.
5. Brush one side of the cabbage steaks with 1 tablespoon of the olive oil and sprinkle with half of the herb mixture. Flip the cabbage and repeat with the remaining 1 tablespoon olive oil and spice mixture.
6. Roast until the cabbage is tender and the edges are brown and crisp, about 15 minutes. Sprinkle with the nuts and continue to roast until the nuts are toasted and the edges and bottom of the cabbage are golden, about 5 minutes more. Drizzle with the lemon juice.